Drink-through lid for a beverage container

ABSTRACT

The present invention is a leak resistant, automatically-sealing, drink-through lid for a beverage container. The lid is capable of being releasably sealably engaged with a top end of the container. The lid includes a tab portion. The tab portion is capable of being depressed so as to provide an opening in the lid. Upon removal of pressure against the tab portion, the tab portion is biased so as to return to a closed position to close the opening. In particular, the tab portion is biased by a curved hinge.

DESCRIPTION OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention is directed to a drink-through lid for a beverage container, such as a cup. More particularly, the present invention relates to a lid that includes a tab or flap portion that is opened when the consumer presses his upper lip to the tab portion and then automatically reseals upon removal of the consumer's lip. Once closed, the tab portion prevents the contents of the beverage container from being spilled. In particular, the tab portion is biased by a curved hinge.

[0003] 2. Background of the Invention

[0004] A large number of prior attempts have been made to produce a non-spill drink lid, as would be used for beverages such as coffee and soft drinks. Such drinks are frequently purchased at fast food establishments, convenience stores, or gas stations, and are often consumed in an automobile.

[0005] Lip operated valves for lids are known in the art. Such a valve is opened by pressure applied by the upper lip of the user which depresses the valve thus permitting the contents of the beverage container to flow through an opening in the lid in a somewhat confined manner. The confined manner inhibits splashing or spreading of the contents while a user is drinking out of the cup.

[0006] An early version of a lip operated valve for a cup lid is disclosed in U.S. Pat. No. 3,927,794, issued to Erdman. This patent discloses a cap having a tab that is formed by molding a line of weakened cross section in the cover section of the cap. Pressure applied to the cap and transmitted to the zone of weakened cross section causes the cap to rupture along that line, thereby forming a depressible tab. The tab is generally defined by a generally U-shaped groove, which includes the line of weakened cross section. In order to facilitate depression of the tab, a raised block is molded integral with the tab adjacent to the closed end of the U-shaped groove. Then, applying gentle pressure to the top of the block causes the weakened portion to tear along the groove until the opening is formed.

[0007] Another lid having a lip operated valve is produced and marketed by Dart Corporation and the subject of U.S. Pat. Nos. 4,412,629 and 4,582,214, issued to Dart et al. These patents disclose a lid having a tab portion formed by a substantially U-shaped slit or line of weakened cross section in or through the lid. The tab portion includes a buttress member integrally formed with the tab portion. In use, the upper lip of the user engages and selectively exerts pressure against the buttress member to depress the tab portion inwardly to provide a drinking opening in the lid. The buttress member includes a plurality of ridges, and arcuate grooves between the ridges, that make insulative contact with the upper lip of a user, thereby protecting the user's lip from burning or scalding due to hot liquid bearing against the bottom surface of the lid. The '629 patent also discloses that the buttress members may be selectively configured to extend over the imaginary bend line of the tab portion so as to enhance the biasing of the tab portion back into its normally closed position. However, the buttress members are not hinges on which the tab portion

SUMMARY OF THE INVENTION

[0008] The present invention is directed to a lid for use on a drinking container. The lid is capable of being releasably sealably engaged with a top end of the container. The lid includes a tab portion, which is capable of being depressed so as to provide an opening in the lid. The tab portion is also biased so as to return to a closed position to close the opening upon removal of pressure against the tab portion. The tab portion is biased by a curved hinge.

[0009] In another embodiment, the lid defines an opening, which is capable of being opened by depressing a tab portion of the lid and is capable of being closed by the tab portion. In addition, the tab portion is capable of being pivoted downward to open the opening at a curved hinge by applying pressure on the tab portion. Also, the tab portion is biased upward by the curved hinge to close the opening upon removal of pressure on the tab portion.

[0010] In yet another embodiment, the lid defines an opening, which is capable of being opened by depressing a tab portion of the lid and is capable of being closed by the tab portion. The tab portion comprises a plurality of edges. One of the plurality of edges comprises a curved hinge, and the other of the plurality of edges are capable of being opened. The tab portion also comprises a top wall and a plurality of side walls. The tab portion is capable of being pivoted downward to open the opening at the curved hinge edge by applying pressure on the tab portion. Also, the tab portion is biased upward by the curved hinge edge to close the opening upon removal of pressure on the tab portion.

[0011] The present invention also provides a method including biasing a tab portion of a lid by a curved hinge. The method may also include releasably sealably engaging the lid with a top end of a container. The method may also include pouring a beverage into the container before releasably sealably engaging the lid with the top end of the container. The method may also include depressing the tab portion so as to provide an opening in the lid. In one embodiment, the biasing step includes removing pressure against the tab portion so that the tab portion returns to a closed position to close the opening.

[0012] In another embodiment, a method of the present invention includes releasably sealably engaging a lid with a top end of a container, depressing a tab portion defined in the lid so that the tab portion pivots downward at a curved hinge so as to provide an opening in the lid, and removing pressure against the tab portion so that the tab portion pivots upward at the curved hinge to return to a closed position to close the lid opening.

[0013] In one embodiment, the curved hinge comprises a groove. In one embodiment, the curved hinge comprising a groove has a V shape.

[0014] In one embodiment, the tab portion comprises a top wall and a plurality of side walls. Each of the plurality of side walls may extend vertically downward from the top wall of the tab portion. In an alternative embodiment, at least one of the plurality of side walls is curved. The at least one side wall that is curved may be the side wall closest to a side wall of the lid and that side wall may be curved outward in a direction toward the side wall of the lid.

[0015] In one embodiment, the top wall of the tab portion is angled upward in a direction from a center of the lid to a side wall of the lid. In another embodiment, the top wall includes a plurality of ribs.

[0016] In one embodiment, the tab portion comprises a plurality of edges, at least one edge is capable of being opened, and at least one other edge comprises the curved hinge. The at least one edge that is capable of being opened may be at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material. The curved hinge edge may comprise a groove, which may have a V shape.

[0017] In one embodiment, when the tab portion returns to the closed position, the tab portion closes to within about 5% of its starting closed position. The starting closed position is before edges of the tab portion are opened. In alternative embodiments, the tab portion closes to within about 2% or about 1% of the starting closed position.

[0018] Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

[0019] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1 is a perspective view of one embodiment of a lid of the present invention, just before the lid is sealably engaged with a beverage container;

[0022]FIG. 2 is a perspective view of the lid shown in FIG. 1, where the lid is sealably engaged with the container, with a tab portion of the lid illustrated in an opened position;

[0023]FIG. 3 is an exploded view of the circled area shown in FIG. 2, illustrating a hinge of the tab portion comprising a V shape groove;

[0024]FIG. 4 is a top plan view of the lid shown in FIG. 1, with the tab portion illustrated in a closed position;

[0025]FIG. 5 is top plan view of the lid shown in FIG. 1, with the tab portion illustrated in the opened position;

[0026]FIG. 6 is a bottom plan view of the lid shown in FIG. 1, with the tab portion illustrated in the closed position;

[0027]FIG. 7 is a bottom perspective view of the lid shown in FIG. 1, with the tab portion illustrated in the closed position;

[0028]FIG. 8 is a bottom perspective view of the lid shown in FIG. 1, with the tab portion illustrated in the opened position;

[0029]FIG. 9 is a perspective view of another embodiment of a lid of the present invention, just before the lid is sealably engaged with a beverage container;

[0030]FIG. 10 is a perspective view of the lid shown in FIG. 9, where the lid is sealably engaged with the container, with a tab portion of the lid illustrated in an opened position;

[0031]FIG. 11 is a top plan view of the lid shown in FIG. 9, with the tab portion illustrated in a closed position;

[0032]FIG. 12 is top plan view of the lid shown in FIG. 9, with the tab portion illustrated in the opened position;

[0033]FIG. 13 is a bottom plan view of the lid shown in FIG. 9, with the tab portion illustrated in the closed position;

[0034]FIG. 14 is a bottom perspective view of the lid shown in FIG. 9, with the tab portion illustrated in the closed position; and

[0035]FIG. 15 is a bottom perspective view of the lid shown in FIG. 9, with the tab portion illustrated in the opened position.

DESCRIPTION OF THE EMBODIMENTS

[0036] Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0037] FIGS. 1-8 illustrate one embodiment of a lid of the present invention. As shown in FIGS. 1 and 2, the present invention is intended to be utilized with a cylindrical beverage container 10. The container 10 includes an open top end 12, a closed bottom end 14, and a surrounding side wall 16 therebetween. The open top end 12 is defined by an annular rim 18 (see FIG. 1) of the container 10. The container 10 used may be made in a variety of sizes corresponding to different sizes of lids of the present invention. More particularly, the annular rim 18 generally has a predetermined dimension or diameter that is coordinated with the dimension or diameter of the lid 20, as described below. The beverage container 10 may be comprised of a variety of materials, including, but not limited to, an insulated plastic material, Styrofoam, or paper material.

[0038] As shown in FIG. 2, the lid 20 is adapted for releasably sealably engaging with the top end 12 of the beverage container 10. Referring to FIGS. 1, 2, and 4-8, the illustrated lid 20 is generally circular in shape. The lid 20 may be in any shape which corresponds to the top end 12 of the container 10. The lid 20 includes a top wall 21, having a top surface 22 (see FIGS. 1, 2, 4, and 5) and a bottom surface 24 (see FIGS. 6-8), and a side wall 26.

[0039] The lid shown in these FIGS. is a “domed” lid. In this embodiment, the side wall 26 includes an engaging portion 26 a for engaging the annular rim 18 of the open top end 12 of the container, and a vertically extending portion 26 b that extends vertically upward from the engaging portion 26 a. The vertically extending portion 26 b spaces the engaging portion 26 a of the side wall 26 from the top surface 22 of the lid 20. The top surface 22 of the lid 20 is generally horizontally disposed proximal to the top of the vertically extending portion 26 b of the side wall 26. Between the top of the vertically extending portion 26 b of the side wall 26 and the top surface 22 of the lid 20, the lid 20 may include an indented rim around the circumference of the lid, which may aid in capturing fluid that has exited the container, to avoid spillage of the fluid.

[0040] Although the lid 20 shown in the FIGS. is a domed lid, it should be appreciated that the lid 20 of the present invention may be a flat lid as well. A flat lid 20 includes a top wall 21, having a top surface 22 and a bottom surface 24, and a side wall 26. The side wall 26 of a flat lid 20, however, is shorter than the side wall 26 of a domed lid 20 shown in the FIGS. The side wall 26 of a flat lid 20 generally includes the engaging portion 26 a of the side wall 26, i.e., that portion that engages with the annular rim 18 of the container 10, and does not include the vertically extending portion 26 b of the side wall 26. Proximal to the top of the engaging portion 26 a, the top surface 22 of the flat lid 20 is horizontally disposed. Between the engaging portion 26 a of the side wall 26 and the top surface 22, the lid 20 may include an indented rim around the circumference of the lid 20, to aid in capturing fluid to avoid spillage thereof.

[0041] The lid 20 may be comprised of a variety of materials, including, but not limited to, plastic or composite material. Similar to the container 10, the lid 20 may be made in a variety of sizes to accommodate a variety of differently sized containers 10. The lid 20 may also be designed to be used with different styles of containers 10.

[0042] As shown in FIGS. 1, 2, and 4-8, the lid 20 includes a tab portion 30. As shown in FIG. 1, in a closed position, the tab portion 30 is raised from the top surface 22 of the lid 20. The tab portion 30 is openable with respect to the top surface 22 of the lid 20. When the lid 20 is sealably engaged with a container 10, and when the tab portion 30 is opened, an opening 28 (see FIGS. 2, 5, and 8) is formed through which the contents of the container 10 may flow through the lid 20. The size of the opening 28 shown in FIGS. 2, 5, and 8 is somewhat exaggerated in order to clearly show the opening 28 in the FIGS.

[0043] As shown in FIGS. 1, 2, and 4-8, the tab portion 30 may be generally square or rectangular in shape. In the embodiment shown, the tab portion 30 includes a plurality of edges 32, 34, and 36, and a hinged edge 38. The edges 32, 34, and 36 are openable relative to the lid 20 to allow the tab portion 30 to pivot open on the hinged edge 38 when a user presses his upper lip against the tab portion 30, as discussed in more detail below. To be openable, the edges 32, 34, and 36 may be, for example, scored or slit, or may be formed of a weakened line of material. The tab portion 30 may take on any art recognized shape including, but not limited to, curvilinear, oval, or round. In addition, the tab portion 30 may include one or more edges that are openable relative to the lid 20.

[0044] As shown most clearly in FIGS. 1, 2, 4, and 5, the hinged edge 38 of the tab portion 30 is curved. In use, the curved hinged edge 38 biases the tab portion 30 to return to a closed position after pressure is removed from the tab portion 30, as discussed below. Because of the curve to the hinged edge 38, the tab portion 30 more readily closes, as compared with a lid having a tab portion with a straight hinge or a lid having a tab portion with no formed hinge. More particularly, while plastic material tends to deform easily, the curved hinged edge 38 gives resistance to the plastic material so that the plastic material has a spring-back quality. In this manner, the curved hinged edge 38 more readily springs back to substantially close the tab portion 30 to close the opening 28 of the lid 20.

[0045] As shown most clearly in FIG. 3, in one embodiment, the hinged edge generally comprises a groove. While the groove may comprise a variety of shapes, in one embodiment, the groove has a V shape. In addition to the curved profile of the hinged edge 38, the profile of a V-shaped groove for the hinged edge 38 also imparts increased rigidity to the hinged edge 38, thereby also aiding in biasing the tab portion 30 to return to the closed position to close the opening 28.

[0046] As shown in FIGS. 1, 2, 4, 5, 7, and 8, the tab portion 30 further includes a top wall 40, and a plurality of side walls 42, 44, 46, and 48. In one embodiment, as shown in FIG. 1, the top wall 40 is angled upward in the direction from the center of the lid 20 to the side wall 26 of the lid 20. Because of the angled top wall 40, when the beverage container 10 is relatively full, the user does not need to tip the beverage container 10 very far from a vertical position in order to drink from the beverage container 10. In addition, the angle to the top wall 40 will allow a proportioned amount of liquid to be consumed by the user relative to the level of the contents in the beverage container 10. As shown in FIGS. 1, 2, 4, and 5, in one embodiment, the top wall 40 of the tab portion 30 includes a plurality of ribs 50 that impart strength to the tab portion 30.

[0047] As shown in FIGS. 1, 2, 7, and 8, in one embodiment, the side walls 42, 44, 46, and 48 are generally flat planar walls that extend vertically downward from the top wall 40 of the tab portion 30, i.e., in the direction toward the container 10 when the lid 20 is sealably engaged on the container 10.

[0048] FIGS. 9-15 illustrate another embodiment of a lid of the present invention. The lid of this embodiment is generally the same as that of the first embodiment and, thus, the discussion set forth above with respect to FIGS. 1, 2, and also generally applies to FIGS. 9-15, respectively. The lid 20 of the second embodiment differs from that of the first embodiment in that, as shown most clearly in FIGS. 9 and 15, one side wall 48 of the tab portion 30, the wall closest to the side wall 26 of the lid 20, is curved to control the amount of fluid to be dispensed from the container 10.

[0049] As shown, this side wall 48 is curved outward, i.e., in the direction toward the side wall 26 of the lid 20. The curve to the wall 48 allows the flow of fluid from the container 10 to be metered in a controlled manner. More particularly, as a user would press his upper lip farther down on the tab portion 30, a larger opening 28 would be formed in the lid 20 to allow more liquid to flow therethrough into, for example, a user's mouth.

[0050] The use of the lid 20 of the both embodiments of the present invention will now be discussed. For the first embodiment, FIGS. 1, 4, 6, and 7 illustrate the tab portion 30 in a closed position, while FIGS. 2, 5, and 8 illustrate the tab portion 30 in an opened position. Similarly, for the second embodiment, FIGS. 9, 11, 13, and 14 illustrate the tab portion 30 in a closed position, while FIGS. 10, 12, and 15 illustrate the tab portion 30 in an opened position.

[0051] After a beverage is poured into the beverage container 10, the lid 20 is snapped into place onto the container 10 to releasably, sealably engage the container 10 and the lid 20. FIGS. 1 and 9 illustrate the lid 20 of each embodiment, respectively, about to be snapped onto a container 10, while FIGS. 2 and 10 illustrate the lid 20 of each embodiment, respectively, snapped onto a container 10.

[0052] Once a user decides that he wants to drink the beverage from the beverage container 10, he would place his lower lip on the side wall 16 of the container 10 below the rim 18 and press his upper lip on the tab portion 30. In one embodiment, the first time the user presses down on the tab portion 30, its edges 32, 34, and 36, which are, for example, scored, slit, or formed of a weakened line of material, are opened with respect to the lid 20. Once these edges 32, 34, and 36 are opened, the downward pressure on the tab portion 30 cause the tab portion 30 to pivot downward on its curved hinged edge 38. This downward movement of the tab portion 30 in turn causes the opening 28 (see, e.g., FIGS. 8 and 15) in the lid 20 to be exposed, which allows the beverage to exit the beverage container 10 into the user's mouth.

[0053] Once finishing that drink, the user removes his upper lip from the tab portion 30, which allows the tab portion 30, which is biased by the hinged edge 38, to return to its substantially closed position, by pivoting upward on the hinged edge 38, thereby closing the opening 28. In one embodiment, the substantially closed position of the tab portion 30 is within about 5% of its starting closed position, i.e., before the edges 32, 34, and 36 are opened. In other words, after pressure is removed from the tab portion 30 and the tab portion 30 springs back to close the opening 28, about 95% of the opening 28 is closed. In another embodiment, the substantially closed position of the tab portion 30 is within about 2% of the starting closed position and when the tab portion 30 springs back to close the opening 28, about 98% of the opening 28 is closed. In another embodiment, the substantially closed position of the tab portion 30 is within about 1% of the starting closed position and when the tab portion 30 springs back to close the opening 28, about 99% of the opening 28 is closed.

[0054] Once the tab portion 30 is in its substantially closed position, the beverage in the container 10 will be prevented from pouring out of the opening 28. The above process may be repeated until all of the contents of the container 10 have exited the container 10.

[0055] The present invention allows for control of the amount of beverage consumed at one time, as well as preventing unwanted spillage of the beverage. It should be appreciated that preventing unwanted spillage, especially of a hot beverage, is important to avoid damaging a user's skin, as well as possibly his clothes.

[0056] At places where a user would buy a beverage in a cup, such as fast food establishments, gas stations, or convenience stores, the cups and lids may be stacked with a lid on each cup (“cup-on-lid stacking”), or by stacking a plurality of cups together and also stacking a plurality of lids together (“lid-on-lid stacking”). It should also be appreciated that, in one embodiment, the use of the tab portion 20 of the present invention does not hinder cup-on-lid stacking because the height of the tab portion 20 is not taller than a false bottom of the cup. Also, it should be appreciated that, in another embodiment, the use of the tab portion 20 of the present invention does not affect the pitch of lid-on-lid stacking.

[0057] While the invention has been described above in connection with a lid that is operated by the lips of a user, it should be appreciated that the present invention may also be manually operated, such by opening the opening in the lid by

[0058] Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. 

What is claimed is:
 1. A lid for use on a drinking container, wherein the lid is capable of being releasably sealably engaged with a top end of the container, comprising: a tab portion, wherein the tab portion is capable of being depressed so as to provide an opening in the lid and wherein the tab portion is biased so as to return to a closed position to close the opening upon removal of pressure against the tab portion; wherein the tab portion is biased by a curved hinge.
 2. The lid of claim 1, wherein the curved hinge comprises a groove.
 3. The lid of claim 2, wherein the curved hinge comprising a groove has a V shape.
 4. The lid of claim 1, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein each of the plurality of side walls extend vertically downward from the top wall of the tab portion.
 5. The lid of claim 1, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein at least one of the plurality of side walls is curved.
 6. The lid of claim 5, wherein the at least one side wall that is curved is the side wall closest to a side wall of the lid and wherein that side wall is curved outward in a direction toward the side wall of the lid.
 7. The lid of claim 1, wherein the tab portion comprises a top wall, wherein the top wall is angled upward in a direction from a center of the lid to a side wall of the lid.
 8. The lid of claim 1, wherein the tab portion comprises a top wall, wherein the top wall includes a plurality of ribs.
 9. The lid of claim 1, wherein the tab portion comprises a plurality of edges, wherein at least one edge is capable of being opened, and wherein at least one other edge comprises the curved hinge.
 10. The lid of claim 9, wherein the at least one edge that is capable of being opened is at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material.
 11. The lid of claim 9, wherein the curved hinge edge comprises a groove.
 12. The lid of claim 11, wherein the curved hinge edge comprising a groove has a V shape.
 13. The lid of claim 1, wherein when the tab portion returns to the closed position, the tab portion closes to within about 5% of its starting closed position, wherein the starting closed position is before edges of the tab portion are opened.
 14. The lid of claim 13, wherein when the tab portion returns to the closed position, the tab portion closes to within about 2% of the starting closed position.
 15. The lid of claim 14, wherein when the tab portion returns to the closed position, the tab portion closes to within about 1% of the starting closed position.
 16. A lid for use on a drinking container, wherein the lid is capable of being releasably sealably engaged with a top end of the container, comprising: an opening defined in the lid, wherein the opening is capable of being opened by depressing a tab portion of the lid and is capable of being closed by the tab portion wherein the tab portion is capable of being pivoted downward to open the opening at a curved hinge by applying pressure on the tab portion; and wherein the tab portion is biased upward by the curved hinge to close the opening upon removal of pressure on the tab portion.
 17. The lid of claim 16, wherein the curved hinge comprises a groove.
 18. The lid of claim 17, wherein the curved hinge comprising a groove has a V shape.
 19. The lid of claim 16, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein each of the plurality of side walls extend vertically downward from the top wall of the tab portion.
 20. The lid of claim 16, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein at least one of the plurality of side walls is curved.
 21. The lid of claim 20, wherein the at least one side wall that is curved is the side wall closest to a side wall of the lid and wherein that side wall is curved outward in a direction toward the side wall of the lid.
 22. The lid of claim 16, wherein the tab portion comprises a top wall, wherein the top wall is angled upward in a direction from a center of the lid to a side wall of the lid.
 23. The lid of claim 16, wherein the tab portion comprises a top wall, wherein the top wall includes a plurality of ribs.
 24. The lid of claim 16, wherein the tab portion comprises a plurality of edges, wherein at least one edge is capable of being opened, and wherein at least one other edge comprises the curved hinge
 25. The lid of claim 24, wherein the at least one edge that is capable of being opened is at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material.
 26. The lid of claim 24, wherein the curved hinge edge comprises a groove.
 27. The lid of claim 26, wherein the curved hinge edge comprising a groove has a V shape.
 28. A lid for use on a drinking container, wherein the lid is capable of being releasably sealably engaged with a top end of the container, comprising: an opening defined in the lid, wherein the opening is capable of being opened by depressing a tab portion of the lid and is capable of being closed by the tab portion; wherein the tab portion comprises a plurality of edges, wherein one of the plurality of edges comprises a curved hinge, and wherein the other of the plurality of edges are capable of being opened; wherein the tab portion comprises a top wall and a plurality of side walls; wherein the tab portion is capable of being pivoted downward to open the opening at the curved hinge edge by applying pressure on the tab portion; and wherein the tab portion is biased upward by the curved hinge edge to close the opening upon removal of pressure on the tab portion.
 29. The lid of claim 28, wherein the curved hinge edge comprises a groove.
 30. The lid of claim 29, wherein the curved hinge edge comprising a groove has a V shape.
 31. The lid of claim 28, wherein each of the plurality of side walls extend vertically downward from the top wall of the tab portion.
 32. The lid of claim 28, wherein at least one of the plurality of side walls is curved.
 33. The lid of claim 32, wherein the at least one side wall that is curved is the side wall closest to a side wall of the lid and wherein that side wall is curved outward in a direction toward the side wall of the lid.
 34. The lid of claim 28, wherein the top wall is angled upward in a direction from a center of the lid to a side wall of the lid.
 35. The lid of claim 28, wherein the top wall includes a plurality of ribs.
 36. The lid of claim 28, wherein the at least one edge that is capable of being opened is at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material.
 37. The lid of claim 28, wherein the tab portion has at least one of a square shape or a rectangular shape.
 38. A method comprising: biasing a tab portion of a lid by a curved hinge.
 39. The method of claim 38, further comprising releasably sealably engaging the lid with a top end of a container.
 40. The method of claim 39, further comprising pouring a beverage into the container before releasably sealably engaging the lid with the top end of the container.
 41. The method of claim 38, further comprising depressing the tab portion so as to provide an opening in the lid.
 42. The method of claim 41, wherein the biasing step comprises removing pressure against the tab portion so that the tab portion returns to a closed position to close the opening.
 43. The method of claim 38, wherein the curved hinge comprises a groove.
 44. The method of claim 43, wherein the curved hinge comprising a groove has a V shape.
 45. The method of claim 38, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein each of the plurality of side walls extend vertically downward from the top wall of the tab portion.
 46. The method of claim 38, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein at least one of the plurality of side walls is curved.
 47. The method of claim 46, wherein the at least one side wall that is curved is the side wall closest to a side wall of the lid and wherein that side wall is curved outward in a direction toward the side wall of the lid.
 48. The method of claim 38, wherein the tab portion comprises a top wall, wherein the top wall is angled upward in a direction from a center of the lid to a side wall of the lid.
 49. The method of claim 38, wherein the tab portion comprises a top wall, wherein the top wall includes a plurality of ribs.
 50. The method of claim 38, wherein the tab portion comprises a plurality of edges, wherein at least one edge is capable of being opened, and wherein at least one other edge comprises the curved hinge.
 51. The method of claim 50, wherein the at least one edge that is capable of being opened is at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material.
 52. The method of claim 50, wherein the curved hinge edge comprises a groove.
 53. The method of claim 52, wherein the curved hinge edge comprising a groove has a V shape.
 54. The method of claim 42, wherein when the tab portion returns to the closed position, the tab portion closes to within about 5% of its starting closed position, wherein the starting closed position is before edges of the tab portion are opened.
 55. The method of claim 54, wherein when the tab portion returns to the closed position, the tab portion closes to within about 2% of the starting closed position.
 56. The method of claim 55, wherein when the tab portion returns to the closed position, the tab portion closes to within about 1% of the starting closed position.
 57. A method comprising: releasably sealably engaging a lid with a top end of a container; depressing a tab portion defined in the lid so that the tab portion pivots downward at a curved hinge so as to provide an opening in the lid; and removing pressure against the tab portion so that the tab portion pivots upward at the curved hinge to return to a closed position to close the lid opening.
 58. The method of claim 57, further comprising pouring a beverage into the container before releasably sealably engaging the lid with the top end of the container.
 59. The method of claim 58, further comprising drinking the beverage out of the container through the lid opening after depressing the tab portion and before removing pressure against the tab portion.
 60. The method of claim 57, wherein the curved hinge comprises a groove.
 61. The method of claim 60, wherein the curved hinge comprising a groove has a V shape.
 62. The method of claim 57, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein each of the plurality of side walls extend vertically downward from the top wall of the tab portion.
 63. The method of claim 57, wherein the tab portion comprises a top wall and a plurality of side walls, and wherein at least one of the plurality of side walls is curved.
 64. The method of claim 63, wherein the at least one side wall that is curved is the side wall closest to a side wall of the lid and wherein that side wall is curved outward in a direction toward the side wall of the lid.
 65. The method of claim 57, wherein the tab portion comprises a plurality of edges, wherein at least one edge is capable of being opened, and wherein at least one other edge comprises the curved hinge.
 66. The method of claim 65, wherein the at least one edge that is capable of being opened is at least one of a scored edge, a slit edge, or an edge formed of a weakened line of material.
 67. The method of claim 65, wherein the curved hinge edge comprises a groove.
 68. The method of claim 67, wherein the curved hinge edge comprising a groove has a V shape. 